This is how I would grade it:

If the Rams win a Super Bowl with Stafford, great trade
If the Rams are constantly fighting to get in the Super Bowl # NFC Championship with losses. good trade
If the Rams win 1 NFC West and are in the playoffs via wild card: I applaud the fact we attempted to better ourselves but we swung and missed.

as far as the Lions, it was a good trade not matter what happens